''Do not confuse it with another fish called the kutum, '' Rutilus kutum ''Rutilus frisii'', the Black Sea roach or kutum, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of freshwater and

brackish water Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuary ...

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

belonging to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Leuciscidae Leuciscidae is a family of freshwater ray-finned fishes, formerly classified as a subfamily of the Cyprinidae, which contains the true minnows. Members of the Old World (OW) clade of minnows within this subfamily are known as European minnow ...

, which includes the daces, Eurasian minnows and related fishes. This fish is found in the

Black Sea The Black Sea is a marginal sea, marginal Mediterranean sea (oceanography), mediterranean sea lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bound ...

basin in Eastern Europe and Western Asia.

Taxonomy

''Rutilus frisii'' was first formally described as ''Leuciscus frisii'' in 1840 by the Finnish

biologist A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual Cell (biology), cell, a multicellular organism, or a Community (ecology), community of Biological inter ...

Alexander von Nordmann Alexander von Nordmann (24 May 1803 in Ruotsinsalmi, Vyborg Governorate – 25 June 1866 in Helsinki, Grand Duchy of Finland) was a Finnish biologist, who contributed to zoology, parasitology, botany and paleontology.Leikola A (2001Nordmann, ...

with its type locality given as "Market in

Odessa ODESSA is an American codename (from the German language, German: ''Organisation der ehemaligen SS-Angehörigen'', meaning: Organization of Former SS Members) coined in 1946 to cover Ratlines (World War II aftermath), Nazi underground escape-pl ...

Danube The Danube ( ; see also #Names and etymology, other names) is the List of rivers of Europe#Longest rivers, second-longest river in Europe, after the Volga in Russia. It flows through Central and Southeastern Europe, from the Black Forest sou ...

, Bug,

Dniester The Dniester ( ) is a transboundary river in Eastern Europe. It runs first through Ukraine and then through Moldova (from which it more or less separates the breakaway territory of Transnistria), finally discharging into the Black Sea on Uk ...

, and

Dnieper The Dnieper or Dnepr ( ), also called Dnipro ( ), is one of the major transboundary rivers of Europe, rising in the Valdai Hills near Smolensk, Russia, before flowing through Belarus and Ukraine to the Black Sea. Approximately long, with ...

rivers". This species is now classified within the genus ''

Rutilus ''Rutilus'', commonly known as roaches, is a genus of freshwater ray-finned fish belonging to the family Leuciscidae, which includes the daces, Eurasian minnows and related fishes. This genus is a widely distributed lineage of leuciscids and r ...

'' in the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Leuciscinae Leuciscinae is a subfamily of freshwater Actinopterygii, ray-finned fishes belonging to the Family (biology), family Leuciscidae, which includes the fishes known as daces, chubs, shiners and minnows. The fishes in this subfamily are mainly found i ...

of the family

. This taxon and the closely related Caspian kutum ('' R. kutum'') of the

Caspian Sea The Caspian Sea is the world's largest inland body of water, described as the List of lakes by area, world's largest lake and usually referred to as a full-fledged sea. An endorheic basin, it lies between Europe and Asia: east of the Caucasus, ...

basin have been considered to be subpopulations of the same species but are now regarded as separate valid species.

Etymology

''Rutilus frisii'' belongs to the genus ''Rutilus'', a name which means "red, golden red and reddish yellow" and is an allusion to the red colour of the fins. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

is an

eponym An eponym is a noun after which or for which someone or something is, or is believed to be, named. Adjectives derived from the word ''eponym'' include ''eponymous'' and ''eponymic''. Eponyms are commonly used for time periods, places, innovati ...

which honours

Bengt Fredrik Fries Bengt Fredrik Fries (24 August 1799, in Helsingborg – 7 April 1839, in Stockholm) was a Swedish zoologist. He studied at Lund University. Works *Observationes entomologicæ (1824) *Beskrifning nya insekter från Colombien (1833). *Skandinavien ...

, a Swedish biologist who is the author of a multi volume work on the fishes of

Scandinavia Scandinavia is a subregion#Europe, subregion of northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. ''Scandinavia'' most commonly refers to Denmark, Norway, and Sweden. It can sometimes also ...

which Nordmann cited in his description of this species.

Description

''Rutilus frisii'' has 11 or 12 soft rays in its

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

and between 12 and 14 soft raysin its

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

. It can be told apart from other roaches occurring in the Black and Caspian sea basins by its almost cylindrical body in which the depth is a fifth to a quarter of the

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

, there are between 53 and 64 scales in the lateral line, the abdomen is rounded to the rear of the pelvic fins, the snout is stout and rounded with a subterminal mouth, there are 9 to branched fin rays on the dorsal fin, the Iris (anatomy)">iris and fins are grey and may have a slight yellowish hue, and breeding males develop large nuptial tubercles scattered on the top and sides of the head. The Black Sea roach has a maximum total length of , although is more typical, and a maximum published weight of .

Distribution and habitat

''Rutilus frisii'' is found in the Black Sea basin and the

Sea of Azov The Sea of Azov is an inland Continental shelf#Shelf seas, shelf sea in Eastern Europe connected to the Black Sea by the narrow (about ) Strait of Kerch, and sometimes regarded as a northern extension of the Black Sea. The sea is bounded by Ru ...

basins, although it is not found in the drainage systems of the Danube and

Kuban Kuban ( Russian and Ukrainian: Кубань; ) is a historical and geographical region in the North Caucasus region of southern Russia surrounding the Kuban River, on the Black Sea between the Don Steppe, the Volga Delta and separated fr ...

river systems. In the Dnieper and lower Bug it is not found upstream from the main dams. In Dniester it has established in reservoirs and the rivers upstream from the reservoirs, while in Don it occurs in the

Tsimlyansk Reservoir Tsimlyansk Reservoir or Tsimlyanskoye Reservoir () is an artificial lake on the Don River in the territories of Rostov and Volgograd Oblasts at . Completed in 1952, the reservoir is one of the largest in Russia, providing power () and irrigation ...

and its lower reaches as well as in the Sea of Azov. In northern

Anatolia Anatolia (), also known as Asia Minor, is a peninsula in West Asia that makes up the majority of the land area of Turkey. It is the westernmost protrusion of Asia and is geographically bounded by the Mediterranean Sea to the south, the Aegean ...

it is known from the major rivers and in the

Rioni The Rioni ( ka, რიონი ; , ) is the main river of western Georgia. It originates in the Caucasus Mountains, in the region of Racha and flows west to the Black Sea, entering it north of the city of Poti (near ancient Phasis). The city ...

and Inguri rivers in

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

. The Black Sea roach can be found in brackish estuaries and the large, freshened plumes of waters discharged from them, coastal lakes which are connected to rivers and the lowland stretches of large rivers. In estuaries they are found in the in deeper layers of water, as deep as , being tolerant to salinities up to 7-12%. There are landlocked populations which permanently live in lakes or reservoirs.

Biology

''Rutilus frissii'' is semi-

anadromous Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousa ...

in which te adults, in non-landlocked populations, move to estuarine environments in Spring, following winter

spawning Spawn is the Egg cell, eggs and Spermatozoa, sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of freely releasing eggs and sperm into a body of water (fresh or marine); the physical act is ...

, and the juveniles do so in their first summer. The adults migrate upstream in late October, halting their migration when the rivers freeze over and recommencing in late winter and early Spring. Spawning takes place in smaller rivers and streams where there is a fast current and a gravel bed, laying large eggs that stick to gravel, rocks and, sometimes, to aquatic pkants. The eggs take 10 to 16 days to hatch. Landlocked populations migrate upstream to spawn in Spring. They feed on zooplankton, algae and insect larvae as juveniles while the adults prey on molluscs, '' Rhithropanopeus'' crabs and other benthic invertebrates, although they do not feed while migrating. spawning or overwintering.

Utilisation

''Rutilus frissii'' is an important species for commercial fisheries, particularly in the Tsimlyansk Reservoir on the Don where it is actually considered to be subject to

overfishing Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing Fish stocks, fish stock), resu ...

References

{{Taxonbar, from=Q606456 Fish described in 1840 Freshwater fish of Europe Freshwater fish Fish of Europe

frisii The Frisii were an ancient tribe, who were neighbours of the Roman empire in the low-lying coastal region between the Rhine and the Ems (river), Ems rivers, in what what is now the northern Netherlands. They are not mentioned in Roman records af ...

Taxa named by Alexander von Nordmann Taxonomy articles created by Polbot